hvac - heating, ventilation and air conditioning€¦ · experienced worker assessment blueprint...

Experienced Worker Assessment Blueprint

HVAC - Heating, Ventilation and Air Conditioning

Test Code: 0144 / Version: 02

HVAC – Heating, Ventilation, and Air Conditioning

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Experienced Worker Assessment Copyright © Nocti Business Solutions, Inc. All Rights Reserved

Specific Competencies and Skills Tested in this Assessment:

Electricity

Demonstrate understanding of basic AC/DC theory

Demonstrate understanding of series/parallel circuits

Use electrical formulas

Interpret symbols on an electrical diagram

Interpret and construct electrical diagrams

Use ohmmeters, voltmeters, ammeters

Identify different electrical components (motor, starter, relays, etc.)

Identify and classify types of electrical motors

Perform troubleshooting

Distinguish between different kinds of wiring diagrams

Apply and manipulate Ohm’s Law

Test motors (and identify motor protection)

Test transformers

Replace 3-phase motors (wire for high and low volts)

Test capacitors and calculate multiple capacitors

Test fuses and calculate size

Soldering, Brazing, and Welding

Identify types of solder and alloys

Choose proper flux for each alloy

Indicate melting temperatures

Prepare materials

Set up and use torch and equipment

Demonstrate techniques of soldering and brazing

Take measurements

Check for leaks

Weld with an arc, MIG, and TIG welder

Weld with a gas welder

Solder sheet metal

Cut with a plasma cutter

Use nitrogen or carbon dioxide when brazing

Braze tubing

Braze copper to brass

Solder tubing


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Specific Competencies and Skills continued:

Air Conditioning

Identify refrigerants by pressures or color codes

Identify types of compressors, condensing units, and evaporator units

Demonstrate understanding of thermodynamic charts

Use refrigerant pressure-temperature charts

Explain concept of Btu (heat)

Demonstrate understanding of heat transfer

Explain a ton of cooling

Use test equipment (refrigerant gauges, temperature meters, etc.)

Use hand tools


Repair and maintain cooling towers

Service air conditioning systems

Measure superheat

Measure subcooling

Demonstrate adjustment of TXV

Test, analyze, and replace compressors

Forced Air, Gas, and Oil Units

Explain theory of operation

Explain temperature rise

Identify type of furnace by air flow

Identify different types of blowers

Identify types of burners

Understand delta T

Identify Btu content of each fuel

Calculate amount of heat in electricity

Identify and use components (high limits, pressure regulators, etc.)

Explain sizing of fuel pipes

Identify difference between conventional and new condensing units

Explain combustion process

Demonstrate methods of cleaning air

Use hand tools


Contrast natural and liquefied petroleum gas

Identify types of gas valves and fittings

Explain principle of operation of pilot proving devices

Determine difference between input Btu and output Btu


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Specific Competencies and Skills continued: Forced Air, Gas, and Oil Units continued:

Adjust for proper operation (gas pressure, primary/secondary air)

Calibrate and adjust thermostat

Adjust air flow, high limit, and fan control settings

Read gas meters

Calculate gas consumption

Determine proper orifice size

Convert from one fuel to another

Use test equipment

Test thermocouples and power piles

Measure gas pressure

Test for combustible gas leaks

Test combustion

Demonstrate reassembly of burner tubes

Demonstrate knowledge of flue installation

Demonstrate knowledge of gas codes

Select components (fuel pumps, nozzles, transformers, electrodes)

Use and adjust barometric dampers

Determine Btu content of fuel oils

Explain operation of high-pressure, gun-type burners

Demonstrate understanding of primary controls

Explain the effects of air in the fuel system

Use test equipment

Install flue systems

Use combustion test equipment

Set electrodes

Demonstrate cleaning of heat exchanger

Demonstrate belt tension adjustment

Remove and install burner assembly

Purge and adjust oil pump

Select single- and dual-stage pumps

Hydronic Systems

Demonstrate understanding of hydronic system operation

Differentiate between types of systems (series loop, monoflow, etc.)

Identify components (regulating valves, safety-relief valves, etc.)

Demonstrate understanding of operating pressures and temperatures

Demonstrate understanding of temperature controls

Use hand tools

Demonstrate understanding of steam traps


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Specific Competencies and Skills continued: Hydronic Systems continued:

Identify heat exchanger types

Demonstrate knowledge of low water cut-offs

Refrigerant Recovery

Define recovery, reclamation, and recycling

Demonstrate knowledge of venting law

Demonstrate proper handling and disposal of refrigerants

Demonstrate knowledge of certification types

Demonstrate use of recovery equipment – passive

Demonstrate use of recovery equipment – active

Explain the Montreal Protocol

Identify refrigerants by chemical family

Heat Pumps and Electric Heat

Demonstrate understanding of refrigeration reversing cycle

Identify different types of defrosting

Identify refrigerant types

Calculate CFM


Service heat pump systems

Demonstrate understanding of emergency heat

Demonstrate understanding of electric furnaces

Identify sequencing contacts and coil

Demonstrate knowledge of wire ampacity

Wire control circuits

Identify types of heat pumps

Pipefitting

Interpret drawing on blueprints

Measure and cut tubing or pipe

Ream or deburr tubing or pipe

Assemble sections of tubing or pipe

Flare tubing

Thread pipe


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Pipefitting continued:

Drill or cut holes for installation of tubing or pipe

Identify valves and fittings

Measure and bend tubing or pipe

Calculate offsets

Demonstrate rigging skills

Install pipe supports

Humidity and Air Movement

Apply fan laws

Balance ductwork system

Identify fittings used in a ductwork system

Determine make-up air requirements

Demonstrate understanding of humidity

Explain the effect of humidity on the movement of air

Distinguish between wet and dry bulb

Use psychometric instruments

Test electronic air cleaners

Test humidifiers

Identify system components

Locate diffuser and return grills

Measure air movement

Design residential duct system

Calculate materials list for a duct system

Fabricate fiberglass duct

Controls

Identify low- and high-pressure controls

Differentiate between a range and a differential adjustment

Explain pressures required to operate an oil safety switch

Differentiate between types of metering valves

Explain the function of a distributor

Explain application, function, and operation or refrigerant controls

Test and set fan and limit controls

Test and calibrate thermostats

Install thermostats

Test cad cells

Test aquastats

Test refrigerant system oil safety controls


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Specific Competencies and Skills continued: Controls continued:

Test motor starting relays

Test defrost system components

Test motor safety controls

Test high/low pressure switches

Installation and Service

Identify and use appropriate hand and power tools

Test, analyze, troubleshoot, and repair system

Service motor components (V-belts, mounts, pulleys, etc.)

Install an A/C system

Install and service forced air systems

Install and service hydronic systems

Install and service heat pump systems

Install and service chilled water systems

Install and service oil fired systems

Demonstrate knowledge of local and state codes

General Safety

Demonstrate ladder safety

Use personal protective wear

Demonstrate fire extinguisher use

Demonstrate safe tools use

Demonstrate electrical safety

Demonstrate safe lifting

Demonstrate reporting accidents

Use goggles/helmet when welding

Demonstrate safe equipment repair practices

Demonstrate eye washing techniques

Related Math and Science

Use temperature conversion scales

Identify modes of heat transfer

Demonstrate understanding of British thermal unit

Explain total enthalpy related to latent and sensible heat

Demonstrate understanding of compression ratio

Explain how compression ratio applies to system efficiency

Demonstrate understanding of gas laws

Chart wet- and dry-bulb temperature


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Specific Competencies and Skills continued: Related Math and Science continued:

Calculate CFM

Measure pressure

Demonstrate understanding of combustion

Calculate duct loss

Calculate structure loss and gain

Calculate area and volume

Demonstrate understanding of balance points

Calculate temperature rise

Calculate solar energy

Determine the solar constant

Measure solar energy

Measure in fractions

Calculate circumference and diameter

Measure pressures

Calculate CFM per ton

Use the psychometric chart

Calibrate temperature- and pressure-measurement equipment

Calculate GPM

Calculate temperature rise

Calculate materials cost

Calculate trigonometry

Interpolate values

Sheet Metal and Ductwork

Demonstrate use of sheet metal table and hand tools

Identify duct materials

Use measurements from blueprints

Layout duct fittings and components

Identify sheet metals (copper, aluminum, galvanized, etc.)

Identify terms IC and IX

Measure sheet thickness

Build metal ducts

Build fiberglass ducts

Determine fiberglass duct application limits

Identify fiberglass duct building tools

Install duct system components

Line ducts

Use duct fasteners

Identify sheet metal tools

Demonstrate knowledge of duct supports


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Employability Skills

Demonstrate CPR

Demonstrate first aid

Prepare a resume

Demonstrate knowledge of blueprint reading

Demonstrate oral presentation

Demonstrate proposal writing

Demonstrate technical writing

Demonstrate use of income tax forms

Apply recordkeeping skills

Demonstrate personal hygiene

Computer Literacy

Demonstrate knowledge of DOS

Demonstrate word processing

Demonstrate use of spreadsheets

Demonstrate knowledge of databases

Use a keyboard to input data


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Written Assessment: Administration Time: 3 hours Number of Questions: 199 Areas Covered:


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Sample Questions: When using a meter to check a load that is not operating, the first check that should be made is A. amperage B. voltage C. resistance D. wattage 50/50 solder has a melting temperature of approximately A. 450 degrees Fahrenheit B. 800 degrees Fahrenheit C. 1100 degrees Fahrenheit D. 1350 degrees Fahrenheit Which of the following is not a system defect of an insufficient heat call? A. fan pulley loose B. fan does not stop running C. fan belt loose or off D. fan too small When operating a steam system, the limit control is known as a/an A. airstat B. pressure control C. flow-trol D. air switch How would a service technician test an aquastat to see when it opens? A. Read a potential difference across the terminals. B. Touch his/her fingers across the points. C. Place a jumper across the terminals. D. Test with an ohmmeter when the pump is running.


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Performance Assessment:

Administration Time: 3 hours Number of Jobs: 2 Areas Covered:

32% Fabricate a Heat Exchanger Interpretation of drawing, measurement and cutting, reaming and deburring, flaring, drilling, soldering, assembly, selection of solder, measurement of parts, performance of leak test and overall quality. 68% Air Conditioning Selection of tools and test instruments, voltage check, connection of refrigeration gauges, identification of compressor terminal sequence, testing of capacitors, measurements of amperage and voltage, recording of pressures, recording of dry bulb air temperature rise and drop, recording of heat strip current draw, recording of suction line temperature, recording of liquid line temperature, diagnosis of restricted liquid line drier, evacuation of liquid line drier, evaporator coil and suction line, checking of system for superheat, subcooling, air temperature, evaporating and condensing temperature difference, removal and reinstallation of unit panels, reading and recording of system pressures.


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Sample Job: Fabricate a Heat Exchanger Maximum Job Time: 1 hour and 30 minutes Participant Activity: The participant will fabricate a heat exchanger in accordance

with the diagram provided in the participant’s test booklet. When finished, the evaluator will pressurize and test the

unit. Proper use of tools and knowledge of safety regulations must be demonstrated.

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